The size limitations of ultra-portable hand-held devices, such as cell phones or PDAs limit the size of the screen area available for viewing information. This makes it hard for users to read textual information using such a device. Various solutions to this problem are being developed in the industry.
There are many methods that have been proposed for viewing documents and web pages on small screens. For example, Woodruff et al., Using thumbnails to search the Web Pages, 198-205, ACM CHI '01, augment web search by automatically increasing the font size of search terms on returned documents. While the authors did not design their system for use on mobile devices, it could be implemented on mobile phone web browsers. However, the described approach does not use text summaries of segmented regions; only increases font size in situ rather than offering multiple different visualizations and interactors and also does not provide mechanisms for visualizing keyphrases across a non-web document.
Berkner et al., Image and Display Dependent Thumbnails, Pages: 53-65, SPIE '04, create a condensed view of a document page, or a SmartNail, by generating a layout with minimal white space that is composed of selected text in a readable size and selected images. In the created condensed view, the original document layout is usually changed. The goal of this study is to create a readable thumbnail for smaller displays such as PDAs. However, in the described system, there is no indexing between different sections and the original text.
The system described in Erol et al., Multimedia Thumbnails for Documents, Pages 231-240, ACM Multimedia '06, automatically creates an animation that pans to important segments on a web page. The described approach also includes audio cues that include keyphrases for the document text as well as figure captions. However, this approach does not augment manual interaction, and relies on audio, which at times may be unavailable or inappropriate.
In M. Hood, E-Newspapers: Digital Deliverance? IEEE Spectrum. February 2007, an iLiad document reader operates to overlay the title and first sentence of news articles on top of the full document.
Hearst's TileBars, described in TileBars: Visualization of Term Distribution Information in Full Text Information Access, Pages: 59-66, ACM CHI '95 (1995), include rows of tiles corresponds to the results of query term sets, where each tile represents a text segment, and the length of a row represents the length of the document. The term frequency is indicated by the gray level of the tile, and the term distribution by these tiles as they appear in the overall graphic representation.
Rattenbury and Canny's CAAD system, described in CAAD: An Automatic Task Support System. Pages: 687-696. ACM CHI '07 (2007), represents collections of documents in a pannable, zoomable interface. However, this system clusters files related to a common activity rather than keyphrases, and the display is not designed for a mobile interface. Additionally, Leuski's Lighthouse, described in Lighthouse: showing the way to relevant information, Pages: 125-130. IEEE InfoVis '00 (2000), is a search engine that presents returned documents with both a flat list and a cluster of spheres positioned according to the similarity of their corresponding documents.
Despite the foregoing advances, the conventional industry approaches are deficient in their ability to facilitate efficient use of displays of small size to render documents in the form convenient for viewing by a user.